The Department of Pathology of Montefiore Medical Center seeks support to participate in collaborative studies for the identification and appraisal of selected cancer cell markers within the framework of the Bladder Cancer Cell Marker Network. This study, benefitting from expertise in urology that will assure acquisition of adequate samples of exfoliated bladder cells from appropriate patients, will 1. test for markers selected to distinguish populations of exfoliated cells, 2. define the marker characteristics and 3. correlate marker expression with tumor behavior. Specifically, the purpose of this proposal is to correlate the expression of selected markers in urothelial cells with behavior of the common non- invasive papillary tumors of the bladder in patients who, after initial surgical tumor excision, are being followed by cystoscopy and cytology without further treatment. High risk patients with carcinoma in situ and/or invasive cancer will not be included. We postulate that the factors governing the natural history of papillary tumors are vested in the urothelium periphera to tumors. Therefore the primary target of this study will be cells in bladder washings voided urines and primary cultures derived from urine obtained during follow-up. The primary markers selected (ras p21 protein, epidermal growth factor receptor and epitectin) have been shown in preliminary studies to discriminate between high and low grade urothelial tumors. The value of additional markers, carcinoembryonic antigen, nuclear proliferation antigen and placental alkaline phosphatase will be explored. About 150 patients will be entered into the study, including 60 old patients who are being followed and 90 new patients. Patients with prostatic hyperplasia and normal adults will be studied as controls. The significance of this study is the identification of patients with the common papillary tumors who may be at high risk for invasive cancer. For low risk patients a reduced frequency of cystoscopic examination is the goal of this study.